Calculate your ideal body weight using the four major clinical formulas: Devine, Robinson, Miller, and Hamwi. Enter height and gender for evidence-based IBW results used in medicine.
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Verified: Devine Formula — Clinical Pharmacology Reference | Robinson (1983) | Miller (1983) | Hamwi (1964) — April 2026
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Calculate your ideal body weight using the four major clinical formulas: Devine, Robinson, Miller, and Hamwi. Enter height and gender for evidence-based IBW results used in medicine.
Ideal Body Weight
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⚠️ Disclaimer: Ideal Body Weight (IBW) is a clinical calculation tool used for drug dosing and medical calculations, not a personal health or beauty standard. IBW does not account for body composition, muscle mass, bone density, or individual health factors. Do not use IBW as a personal weight-loss target. Consult a healthcare provider for personalized weight and health guidance.
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Sources & Methodology
✓ Formulas and data verified against authoritative sources listed below.
Robinson formula for IBW published in DICP: The Annals of Pharmacotherapy
Methodology: Four clinical IBW formulas applied: Devine (1974): Male = 50 + 2.3 x (height_in - 60); Female = 45.5 + 2.3 x (height_in - 60). Robinson (1983): Male = 52 + 1.9 x (in-60); Female = 49 + 1.7 x (in-60). Miller (1983): Male = 56.2 + 1.41 x (in-60); Female = 53.1 + 1.36 x (in-60). Hamwi (1964): Male = 48 + 2.7 x (in-60); Female = 45.4 + 2.2 x (in-60). All results in kg; converted to lbs by multiplying by 2.2046.
⏱ Last reviewed: April 2026
How to Calculate Ideal Body Weight
Ideal body weight (IBW) is a clinical metric used primarily for medication dosing (chemotherapy, renal dosing, anesthesia), ventilator settings, and nutritional calculations. There are four major IBW formulas — Devine, Robinson, Miller, and Hamwi — each developed independently and each giving slightly different results. No single formula is universally accepted as most accurate for all purposes.
The Four Major IBW Formulas
Devine (1974) is the most widely used clinically, especially for drug dosing. Robinson (1983) was developed as a refinement of Devine. Miller (1983) tends to give slightly higher values. Hamwi (1964) uses a different baseline and increment. All four formulas use height above 5 feet (60 inches) as the key variable, with gender-specific base values and per-inch increments.
Clinical Uses of Ideal Body Weight
IBW is used in medicine for: 1) Drug dosing — many medications are dosed by IBW not actual body weight to avoid overdosing obese patients. 2) Ventilator tidal volume settings — 6-8 mL/kg IBW is the lung-protective ventilation standard. 3) Nutritional support — caloric needs are often calculated from IBW or adjusted body weight. 4) BMI comparison — comparing actual weight to IBW gives context about degree of over- or under-weight.
IBW vs. BMI vs. Healthy Weight Range
IBW gives a single target weight. BMI provides a range (18.5-24.9 is normal). The healthy weight range for a given height spans about 30-40 lbs. IBW typically falls in the middle of the BMI-normal weight range but may not account for muscle mass, body composition, or individual variation. For personal health goals, work with a healthcare provider rather than targeting an IBW number.
Adjusted Body Weight (ABW)
For patients who are significantly overweight, adjusted body weight (ABW) is used instead of IBW for some calculations. ABW = IBW + 0.4 x (Actual Body Weight - IBW). This accounts for the fact that adipose tissue still requires some perfusion and metabolic support. Lean body weight (LBW) is another variant used in specific clinical contexts.
Devine Male: IBW = 50 + 2.3 x (height in - 60) | Devine Female: IBW = 45.5 + 2.3 x (height in - 60)
All formulas in kg. Robinson Male: 52 + 1.9 x (in-60). Robinson Female: 49 + 1.7 x (in-60). Miller Male: 56.2 + 1.41 x (in-60). Miller Female: 53.1 + 1.36 x (in-60). Hamwi Male: 48 + 2.7 x (in-60). Hamwi Female: 45.4 + 2.2 x (in-60). Convert kg to lbs: multiply by 2.2046.
Ideal Body Weight by Height — Devine Formula
Height
IBW Male (Devine)
IBW Female (Devine)
IBW Male (lbs)
IBW Female (lbs)
5 ft 0 in (60 in)
50.0 kg
45.5 kg
110.2 lbs
100.3 lbs
5 ft 2 in (62 in)
54.6 kg
50.1 kg
120.4 lbs
110.5 lbs
5 ft 4 in (64 in)
59.2 kg
54.7 kg
130.5 lbs
120.6 lbs
5 ft 6 in (66 in)
63.8 kg
59.3 kg
140.7 lbs
130.7 lbs
5 ft 8 in (68 in)
68.4 kg
63.9 kg
150.8 lbs
140.9 lbs
5 ft 10 in (70 in)
73.0 kg
68.5 kg
161.0 lbs
151.0 lbs
6 ft 0 in (72 in)
77.6 kg
73.1 kg
171.1 lbs
161.2 lbs
6 ft 2 in (74 in)
82.2 kg
77.7 kg
181.3 lbs
171.3 lbs
💡 Clinical Note: IBW formulas were developed in the 1960s-1980s primarily for medication dosing in typical-weight patients. They are less accurate for children, very short or very tall individuals, and those with unusually high or low muscle mass. For athletic individuals, actual body weight or lean body weight may be more appropriate for some calculations.
Frequently Asked Questions
Ideal body weight (IBW) is a calculated weight based on height and gender, used primarily in clinical medicine for drug dosing, ventilator settings, and nutritional calculations. It is not a personal fitness goal but a pharmacological reference value. The Devine formula is most commonly used: Male IBW = 50 + 2.3 x (height in inches - 60) kg.
Using the Devine formula: Male: IBW (kg) = 50 + 2.3 x (height in inches - 60). Female: IBW (kg) = 45.5 + 2.3 x (height in inches - 60). Convert to lbs by multiplying by 2.2046. Example: 5 ft 10 in male = 50 + 2.3 x 10 = 73 kg = 160.9 lbs.
The Devine formula (1974): Male IBW = 50 + 2.3 x (height in inches - 60) kg. Female IBW = 45.5 + 2.3 x (height in inches - 60) kg. For heights at or below 5 feet (60 inches), IBW = the base value (50 kg male, 45.5 kg female) with no increment. This formula is the most widely used in clinical pharmacology.
All three use height above 60 inches as the variable with gender-specific base values, but they differ in base weight and per-inch increment. Devine: male base 50 kg, 2.3 kg/inch. Robinson: male base 52 kg, 1.9 kg/inch. Hamwi: male base 48 kg, 2.7 kg/inch. Results typically differ by 2-8 kg depending on height.
Not exactly. IBW is a clinical calculation for medical purposes. Healthy weight is typically defined using BMI (18.5-24.9 normal range). IBW usually falls within the normal BMI range but is a single point rather than a range. Healthy weight also depends on body composition, muscle mass, and individual factors not captured by either metric.
IBW is used for: medication dosing (especially renally-cleared drugs, chemotherapy, aminoglycosides), lung-protective ventilation settings (6 mL/kg IBW tidal volume), nutritional support calculations, anesthesia drug dosing, and kidney disease staging (eGFR calculations use body surface area derived from height and weight).
Adjusted body weight (ABW) = IBW + 0.4 x (Actual Body Weight - IBW). It is used when actual body weight significantly exceeds IBW, as adipose tissue still requires some blood flow and metabolic support. ABW is used for some drug dosing calculations in patients with obesity.
IBW formulas are estimates developed from population data in the 1960s-1980s. They are most accurate for average-height adults. They tend to underestimate ideal weight for very tall individuals and have limited applicability to children, athletes, or those with unusual body compositions. Multiple formulas should be considered together, not one alone.
Using Devine: 6 ft = 72 inches. IBW = 50 + 2.3 x (72-60) = 50 + 2.3 x 12 = 50 + 27.6 = 77.6 kg = 171 lbs. Robinson gives 52 + 1.9 x 12 = 74.8 kg = 165 lbs. The average of all four formulas is approximately 78 kg (172 lbs).
IBW is a medical reference metric, not a personal fitness goal. Many healthy people fall above or below their calculated IBW due to differences in muscle mass, bone density, and body composition. Focus on overall health markers (blood pressure, blood sugar, cholesterol, energy levels) rather than targeting a specific IBW number.